The scope of the present invention is that of telescoped-type munitions.
These munitions usually comprise a casing composed of a cylindrical tube, having a plug at each end, in which a projectile and propelling charge are placed.
The projectile is entirely enclosed by the casing and means to ensure that it is held in its position, axially and radially, with respect to the casing envelope must be provided.
Patent FR2679991 describes different means enabling the projectile to be held axially with respect to the envelope.
These means can comprise a rear stop carried by a primer and a front stop constituted by an elastic ring placed in a groove of the front plug.
There are several disadvantages to this solution.
When the munition is being fired the front and back plugs move with respect to the envelope with the danger of causing the projectile to tilt thereby impeding the correct loading of the projectile in the gun barrel.
Document FR2679991 describes other holding means which combine a stop surface fitted on the front plug and an elastic ring placed in a groove in the same plug.
The problem wherein the projectile tilts when the plugs move is thereby avoided.
However, firing tests have demonstrated that the use of an elastic ring was causing disturbances in the projectile.
In fact such rings are usually fitted with a slit enabling them to be inserted into a groove and this slit constitutes an asymmetric band on the ring.
When the projectile is fired the ring does not fracture symmetrically because of its slit. This causes a shock to the projectile which does not follow the axial direction of the latter.
Such a shock disrupts loading in the gun barrel and the later ballistic reaction of the projectile.